queryLogic.isDefinedAndHasMembers(query)

Returns the query object if query can have records. It returns true if the query is not EMPTY, UNDEFINABLE, or UNKNOWABLE.

import {QueryLogic} from "can";
const queryLogic = new QueryLogic();

const emptyObject = queryLogic.isDefinedAndHasMembers({});
console.log( emptyObject ); //-> {}

const universal = queryLogic.isDefinedAndHasMembers(QueryLogic.UNIVERSAL);
console.log( universal ); //-> QueryLogic.UNIVERSAL

const undefinable = queryLogic.isDefinedAndHasMembers(QueryLogic.UNDEFINABLE); 
console.log( undefinable );//-> false